Yearbook Color Management Matthew Bernius Rochester Institute of Technology School of Print Media Topic Overview Color in Theory Color in Production Color Management Image Editing (best practices) 1
Color in Theory Color perception is subjective We all perceive color slightly differently Relative to our vision The rods and cones in our eyes vary what we see Relative to our experiences Where we grew up, the memories we carry will change our response to the color we perceive and determine our expectations for the color we want Color in Production Color reproduction is objective. Each device renders color in a specific way Monitor to monitor to monitor... Printer to printer to printer... The same printer with different paper or ink 2
Color in Production Software works the same way... When we work on an image file, we think image while the software only sees file In software, all colors we see are actually specified only as numbers Each color is derived from a combination of pixels with precise values Color Theory: Additive Color Additive color assumes that we start in the dark. As you add more and more light (RGB) energy, you mix colors and build to white Cameras, scanners and computer monitors all utilize additive color 3
Color Theory: Additive Color The primaries for additive color are red, green and blue (RGB) Note: The labels here are shown in percent (0-100%) rather than the 0-255 scale that RGB uses natively. Color Theory: Subtractive Color Subtractive color works on the premise that white light (RGB) is going to reflect off a printed surface The color that is perceived is determined by which parts of the white light the colored ink (CMY) absorbs and reflects 4
Color Theory: Subtractive Color The primaries for subtractive color are cyan, magenta and yellow (CMY) In modern printing, we also include black ( K ) to insure dark neutral shadows Additive vs. Subtractive Color A typical CMYK press gamut is shown here as the solid. The wireframe displays an RGB color gamut typically used in production 5
Additive vs. Subtractive Color The difference between RGB and CMYK causes many of the problems when trying to match monitor to print Color management was developed to address the issue directly... Color Management Color management was developed in the early 1990 s to address the differences between color in digital systems The intent of color mgmt. is to provide for consistent and predictable color It does not insure that WYSIWYG... 6
Color Management Color management works by providing a numeric link between color devices Devices like monitors, printers That link is the color profile Color Management Color profiles are used to describe the exact color behavior of a device For color mgmt to work, each device in the production chain needs to have a color profile that accurately describes it 7
Color Management The most accurate profiles are made by the end-user using color measurement tools and software Most people use profiles supplied by the software or a vendor Color Management Whether or not you know they are there, profiles are used on every device Some software lets you turn color mgmt off but, in reality, it is always on at some level 8
Color Management The best way to manage your color is to set your software up to always use profiles the same way Follow this practice by using a standard method to adjust images as well Setting Up Color Management Edit/Color Settings in Adobe Photoshop 9
Using Color Management For most yearbook workflows, you ll want to use the srgb color profile for all image and graphic files Most cameras shoot to srgb natively, most desktop printers expect to print from it Using Color Management To get your monitor view to more closely match the press s CMYK color profile, you ll have to use the View/Proof Setup feature in Photoshop View/Proof Setup/Custom 10
Using Color Management Under Device to Simulate, select the profile for the press your yearbook is being printed on If you don t have it, use the U.S. Web Coated (SWOP) v2 Using Color Management This Proof Setup feature is designed to help you see what your colors will look like as they will be printed It should be applied prior to doing image editing and color correction 11
Monitor Calibration If you have the ability to calibrate your monitor, do it. It can only help. But... Monitor calibration only insures the monitor view is consistent It does not relate the monitor view to the press or any printer View/Proof Setup does this... Color Conversion (RGB to CMYK) When you convert a file from RGB to CMYK, you are using two profiles This conversion should be done: Only after all image editing is compete Only when you know what CMYK setting to use (your printer s or SWOP CMYK) 12
Image Editing: Best Practices The order for editing images is standard Here s the workflow to follow Adjust highlight Adjust shadow Adjust midtones Adjust color Convert to B&W or CMYK Image Editing: Best Practices If you are using Photoshop... Always use Adjustment Layers Allows for flexibility during editing Allows you to earn without hurting the file Allows for the undoing of any change so long as the layers are still not Flattened 13
Image Editing: Best Practices Let s look at a few examples... [demo] Summary Getting the color you want begins with an understanding that the systems we use to reproduce color are very precise They render color based on science & math Applying a simple, systematic approach to color helps improve your chances of getting the color you want in the end 14
Questions? http://cias.rit.edu/printmedia/yearbook email michael.riordan@rit.edu 15